# Lactotroph.ode # This XPPAUT file contains the program for the activity of a # pituitary lactotroph as described in the paper "The Relationship Between Two # Fast/Slow Analysis Techniques for Bursting Oscillations", W. Teka, J. Tabak, # R. Bertram, Chaos, 22:043117, 2012. # Variables: # v -- membrane potential # n -- delayed rectifier K current activation # c -- calcium concentration v(0)=-60 n(0)=0.1 c(0)=0.1 par auto=0, cpar=0.8 par vn=-5, kc=0.16, ff=0.01, par vca=50, vk=-75, gk=4, Cm=5, gf=0.4 par gcal=2, gsk=1.7 par vm=-20, vf=-20 par sn=10, sm=12, sf=5.6 par taun=43, ks=0.5, alpha=0.0015 # use auto=0 for simulation # use auto=1 to make bifurcation diagram with Ca as parameter (cpar) %cd=(1-auto)*c+auto*cpar phik=1/(1+exp((vn-v)/sn)) phif=1/(1+exp((vf-v)/sf)) phical=1/(1+exp((vm-v)/sm)) cinf=c^2/(c^2+ks^2) ica=gcal*phical*(v-vca) isk=gsk*cinf*(v-vk) ibk=gf*phif*(v-vk) ikdr=gk*n*(v-vk) ik = isk + ibk + ikdr v'= -(ica+ik)/Cm n'= (phik-n)/taun c'= -ff*(alpha*ica+kc*c)*(1-auto)+auto*(cpar-c) %aux aical=ica %aux aidr=ikdr %aux aisk=isk %aux aibk=ibk %aux iktot=ik %aux ca=cd aux sinf=cinf aux gf=gf aux gk=gk aux tsec = t/1000 %aux itot=ik+ica %@ dt=10, total=200000, maxstor=200000 %@ bounds=10000000, xp=tsec, yp=v, bell=off %@ xlo=0, xhi=60000, ylo=-80, yhi=25 @ dt=0.1, total=60000, maxstor=200000 @ bounds=1000000000, xp=t, yp=v @ xlo=0, xhi=3000, ylo=-85, yhi=10, bell=off @ Ntst=70, Nmax=1000, Npr=1500, parmin=-1, parmax=200,Dsmax=0.2 done